U.S. patent number 4,080,480 [Application Number 05/694,260] was granted by the patent office on 1978-03-21 for catalyzing cellulosic textile finishing processes with phosphonic acid derivatives.
This patent grant is currently assigned to The United States of America as represented by the Secretary of. Invention is credited to Donald J. Daigle, Russell M. H. Kullman, Robert M. Reinhardt.
United States Patent |
4,080,480 |
Reinhardt , et al. |
March 21, 1978 |
Catalyzing cellulosic textile finishing processes with phosphonic
acid derivatives
Abstract
Alkyl and aryl phosphonic acids and certain salts thereof have
been found useful as catalysts for the chemical reactions involved
in finishing cotton and other cellulosic textiles. These versatile
catalysts can be employed in a variety of finishing treatments
including dimensional stability, durable press, and flame
resistance and are operative under a diverse range of processing
conditions.
Inventors: |
Reinhardt; Robert M. (New
Orleans, LA), Kullman; Russell M. H. (Metairie, LA),
Daigle; Donald J. (New Orleans, LA) |
Assignee: |
The United States of America as
represented by the Secretary of (Washington, DC)
|
Family
ID: |
24788081 |
Appl.
No.: |
05/694,260 |
Filed: |
June 9, 1976 |
Current U.S.
Class: |
427/393.2;
427/381; 427/382; 427/393.3; 8/181; 8/184 |
Current CPC
Class: |
D06M
15/45 (20130101) |
Current International
Class: |
D06M
15/45 (20060101); D06M 15/37 (20060101); B05D
003/02 () |
Field of
Search: |
;427/39C,381,382
;8/116P,184 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gwinnell; Harry J.
Attorney, Agent or Firm: Silverstein; M. Howard McConnell;
David G. Cangemi; Salvador J.
Claims
We claim:
1. In a process for finishing a textile material containing at
least 50% cellulosic fiber to impart wrinkle resistant properties,
said process of the type comprising impregnating the textile with
an aqueous formulation of an N-methylol amide crosslinking agent
and a catalyst, drying, and curing the impregnated textile, the
improvement characterized by:
substituting as the catalyst in said formulation a monomeric
phosphonic acid derivative having less than 8 carbons, selected
from the group consisting of
methylphosphonic acid,
chloromethylphosphonic acid,
trichloromethylphosphonic acid,
phenylphosphonic acid,
magnesium acid methylphosphonate,
magnesium methylphosphonate,
magnesium acid chloromethylphosphonate,
magnesium acid trichloromethylphosphonate,
ammonium acid methylphosphonate,
ammonium acid chloromethylphosphonate,
ammonium acid trichloromethylphosphonate, and
diammonium phenylphosphonate
to provide a wide versatility in the selection of curing
conditions.
2. The improved process of claim 1 wherein the phosphonic acid
derivative is ammonium acid methylphosphonate.
3. The improved process of claim 1 wherein the phosphonic acid
derivative is ammonium acid chloromethylphosphonate.
4. The improved process of claim 1 wherein the phosphonic acid
derivative is ammonium acid trichloromethylphosphonate.
5. The improved process of claim 1 wherein the phosphonic acid
derivative is diammonium phenylphosphonate.
Description
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to finishing processes for textiles, and
more particularly to the use of phosphonic acid derivatives as
catalysts in the treatment of cellulose-containing materials with
agents to give dimensional stability, durable press, and flame
resistant textile products.
It is well known that dimensional stability, durable press, and
flame resistance of cellulose-containing textiles can be enhanced
by suitable treatment of such materials with certain chemical
agents. The chemical agents employed in such treatments generally
require catalysts to affect reaction with the cellulosic component
to achieve improvement of the desirable properties in the finished
products. Considerations of cost, efficiency, compatibility,
toxicity, pollution effects, and many other factors have limited
the scope of catalysts acceptable in finishing operations. Those
catalysts widely employed in the processing of textiles for durable
press, for instance, are not normally useful in other
processes.
(2) Description of the Prior art
In the prior art we find reference to at least three finishing
processes reportedly useful in producing products with improved
dimensional stability, durable press performance, and flame
resistance. These processes are mild cure, damp or moist cure, and
pad-dry-cure finishing procedures. The latter process, and with
modifications thereof, has been the most widely practiced
commercially.
Mild cure and damp cure processes were developed as rather special
techniques particularly to achieve high wet wrinkle resistance.
These processes require catalysts that normally are not acceptable
for use in other processes. In general, catalysts for these two
processes were prepared by moderating mineral acids, as acids alone
required very precise control of treatment conditions to avoid
overcuring and severe strength loss.
Mild cure finishing is accomplished by padding fabric with a
chemical agent to react with cellulose and strong catalyst, then
heating the wet, impregnated fabric at about 60.degree.-100.degree.
C for a short time without a pre-drying step. Detailed description
of this process is given in the Textile Chemist and Colorist,
Volume 1, page 415, 1969, and Volume 2, page 337, 1970.
Damp or moist cure finishing is similar to mild cure finishing in
that a chemical agent and a strong catalyst are applied to fabric
but then moisture content is carefully reduced to the range of
6-12%, after which fabric is sealed in a package to prevent
moisture loss and held at room temperature for 12-24 hours, then
neutralized and washed. More specific description of this process
is given in U.S. Pat. No. 3,409,462.
Pad-dry-cure finishing follows the sequence of impregnating fabric
with a chemical agent and catalyst, drying at a moderately elevated
temperature, generally not exceeding about 100.degree. C, then
curing at temperatures of 150.degree. to about 180.degree. C.
In the widely used pad-dry-cure process, Lewis acid type catalysts
have been dominant in durable press finishing. Two salts, zinc
nitrate and magnesium chloride, have been the principal catalysts
used by industry.
A serious problem exists in the textile industry with the two
catalysts most widely used in wrinkle resistant finishing, zinc
nitrate and magnesium chloride. Several geographical areas have
either banned or heavily restricted the use of zinc nitrate or any
heavy-metal salt because plant effluents cause stream pollution.
Also, many finishers have found that nitrate catalysts can cause
shade changes with certain dyestuffs or yellowing on some white
goods. Many textile plants can no longer use magnesium chloride or
any halide-containing catalyst for fear of generation of
bis(chloromethyl) ether which has been designated as carcinogenic.
In addition, fuel and chemical shortages are causing finishers to
seek catalysts that allow processing to be conducted with lower
curing temperatues and faster curing times in an effort to conserve
energy.
Traditionally, chemical finishing treatments to produce flame
resistance also have been carried out by the pad-dry-cure process.
Catalyst systems usually consist of some type of Lewis acid or
combination of a Lewis acid and an organic acid but there are no
outstanding catalysts that dominate this field. Sanderson et al,
Textile Research Journal 40, pages 217-222 (1970) have employed
lower dialkyl and trialkyl phosphites as phosphonate precursors to
become a substantial part of the ultimate flame resistant product
but these phosphites are reactive agents and not catalysts. Wedell,
U.S. Pat. No. 2,953,481, teaches the use as catalysts of
high-molecular phosphonic acid salts that are derived from
low-molecular aliphatic amines, diamines, oxyalkylamines, etc.
which are volatile or readily react with formaldehyde. However,
only phosphonic acids of at least 8 carbon atoms are operative in
the Wedell disclosure. Sommer et al, U.S. Pat. No. 3,219,407,
describe the use of copolymers of vinyl phosphonic acid of 50-100
molecular units as catalysts in creaseproofing cellulose textiles
and claim improved strength in the finished product. Monomeric,
saturated phosphonic acids were not so employed.
While the treatments and processes described above impart highly
desirable properties to cellulose-containing textiles, there are a
multitude of catalysts required, and no one specific class is
satisfactory in all cases.
SUMMARY OF THE INVENTION
It is an object of this invention to provide an improvement in the
treatment of cellulosic textile materials by a wide variety of
finishing systems and techniques to impart desirable properties
through the use of phosphonic acid derivatives as catalysts in said
finishing treatments.
We have now found that phosphonic acid derivatives of the lower
molecular structures, that is, those having less than 8 carbons,
are effective catalysts in finishing treatments applied to
cellulose-containing textiles from aqueous formulations with
processing under a wide selection of curing conditions and
techniques. The free acids of alkyl and aryl phosphonic acids and
their magnesium and ammonium salts are excellent catalysts for
treatments with agents to impart dimensional stability, durable
press, and flame resistance to textile materials.
In summary, this invention provides a class of catalysts based on
phosphonic acid derivatives, either in the free acid or a salt
form, that are effective in treatments of cellulose-containing
textiles with chemical agents following procedures of any one of
several different finishing processes to impart desirable
properties of dimensional stability, durable press, and flame
resistance.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred form for treatment is fabric but textile material may
be in other forms such as fibers or yarns. In fabric form,
composition of the fibers may be varied with a minimum of 50% as
the cellulosic fiber. The cellulosic component may be either
natural or man-made.
The chemical agents employed with the phosphonic acid derivatives
to produce crosslinked fabrics with improved dimensional stability
and durable press properties are selected from N-methylol amide
compounds such as dimethylol compounds of ureas, ethyleneurea,
dihydroxyethyleneurea, urons, triazones, pyrimidones, melamines,
carbamates and the like with the preferred agent being dimethylol
dihydroxyethyleneurea at concentrations ranging from about 8% to
30% by weight of the treatment bath. Formulations for producing
flame resistant fabric may be selected from combinations of
tetrakis(hydroxymethyl)phosphonium hydroxide (THPOH), urea, and
trimethylol melamine (TMM) with a preferred molar ratio of these
agents consisting of 6:5:1, respectively, at concentrations of this
preferred ratio of agents ranging from about 25% to about 40% of
the treatment bath.
The phosphonic acid derivatives suitable for this invention include
alkyl and aryl derivatives having less than 8 carbons, their
magnesium salts, and their ammonium salts. It is also within the
scope of this invention to employ phosphonic acids with modified
alkyl groups attached to the phosphorus atom in the acid, as for
instance, a haloalkyl group, and magnesium and ammonium salts of
the modified alkyl phosphonic acids. Preferred compounds of this
nature are chloromethyl phosphonic acid and trichloromethyl
phosphonic acid. Concentrations of catalysts may range from about
0.1 to about 30 millimoles per 100 g of treatment solution with a
preferred range of 0.5 to 20 millimoles catalyst per 100 g
solution.
Curing temperatures from about 100.degree. to about 200.degree. C
are satisfactory with a preferred upper limit of 175.degree. C at
times ranging from about 1 minute to about 4 minutes, the longer
times being preferred for the lower temperatures.
The following examples further describe the invention and are given
as illustrations and should not be considered as limiting the
scope.
Properties of the fabrics were determined by known test methods:
durable press (DP) ratings after machine washing and tumble drying
by AATCC Test Method 124-1968, procedure III-B; wrinkle recovery
angles by AATCC Test Method 66-1968; breaking strengths by ASTM
D1682-64; nitrogen by the Kjeldahl method; and phosphorus content
by X-ray fluoresence as described by Tripp et al in Textile
Research Journal 34, page 773-777 (1964). The match test, a widely
used test by those skilled in the art for testing flame resistance,
is described by Reeves and coworkers in the Textile Research
Journal 23, page 257 (1957).
The increased fabric weight due to padding times 100, divided by
the initial sample weight, is the percent wet pickup; the increased
fabric weight due to the treatment, times 100, divided by the
initial sample weight, is percent add-on; and efficiency of add-on,
in percent, was determined by dividing the amount of nitrogen in
the finished sample, times 100, by the amount of nitrogen applied
in padding as determined from wet pickup of the treatment
solution.
EXAMPLE 1
To 2.9 g (50 millimoles) of magnesium hydroxide, 15.3 g (100
millimoles) of 85% chloromethylphosphonic acid was added slowly,
and the solution was brought to 100 ml volume with water. This
stock solution contained 0.5 millimole of magnesium acid
chloromethyl phosphonate, ##STR1## per 100 ml of solution.
To 1.45 g (25 millimoles) of magnesium hydroxide was added slowly
10.9 g (50 millimoles) of trichloromethylphosphonic acid, ##STR2##
then the solution was brought to 100 ml volume with water. This
stock solution contained 0.25 millimole of magnesium acid
trichloromethylphosphonate, ##STR3## per ml of solution.
To 2.85 g (50 millimoles) of aqueous 29.8% (wt/wt) NH.sub.3 was
added slowly 7.68 g (50 millimoles) of 85% chloromethylphosphonic
acid, then the solution was brought to 100 ml volume with water.
This stock solution contained 0.5 millimole of ammonium acid
chloromethylphosphonate, ##STR4## per ml of solution.
To 2.85 g (50 millimoles) of aqueous 29.8% (wt/wt) NH.sub.3 was
added slowly 10.9g (50 millimoles) of trichloromethylphosphonic
acid, then the solution was brought to 100 ml volume with water.
This stock solution contained 0.5 millimole of ammonium acid
trichloromethylphosphonate, ##STR5## per ml of solution.
5.44 g (25 millimoles) of trichloromethylphosphonic acid were
dissolved in water and diluted to 100 ml volume. This stock
solution contained 0.25 millimole of trichloromethylphosphonic
acid, ##STR6## per ml of solution.
3.84 g (25 millimoles) of 85% chloromethylphosphonic acid were
dissolved in water and diluted to 100 ml volume. This stock
solution contained 0.25 millimole of chloromethylphosphonic acid,
##STR7## per ml of solution.
Treatment solutions were prepared such that each 100 g of solution
contained 9 g of dimethylol dihydroxyethyleneurea (DMDHEU) with a
catalyst. The catalyst concentrations in the treatment baths were
varied by pipetting in different amounts of the stock
solutions.
Cotton printcloth samples were passed into and through the
treatment baths and through squeeze rolls to achieve wet pickups of
about 85%. The wet, impregnated fabrics were pinned on frames,
dried for 7 minutes at 60.degree. C and cured for 3 minutes at
160.degree. C, in a forced air-circulation oven, machine washed and
tumble dried.
Table I identifies the catalyst and its concentration in millimoles
(mmol) per 100 g of treatment bath and shows DP ratings after
tumble drying. To those skilled in the art, it is well known that
improvement in fabric dimensional stability and/or smooth drying
performance may be qualitatively measured by determination of DP
rating of treated fabric.
In Table I are shown the operative catalyst concentration ranges to
improve dimensional stability of fabric (DP ratings of finished
samples are greater than the untreated sample). To achieve
satisfactory durable press performance in fabric according to those
skilled in the art, a rating of 3 or higher is required. Minimum
levels of catalyst concentration to achieve the desired DP level
are 2 millimoles per 100 g of treatment bath for the free acids and
2.5 millimoles per 100 g of treatment bath for the magnesium salts
and the ammonium acid salts of each acid derivative.
TABLE I ______________________________________ Mmol/100 g DP
Ratings of Fabric Treated with Catalysis by: treatment ammonium
bath free acid magnesium acid salt acid salt
______________________________________ (Chloromethylphosphonic acid
type catalysts) 0.5 2.0 -- -- 1 2.9 2.0 2.5 2 3.5 -- -- 2.5 -- 3.4
3.3 3 4.3 -- -- 5 4.5 4.2 3.8 7.5 -- 3.9 4.2 10 -- 4.3 4.3 15 --
4.4 4.3 (Trichloromethylphosphonic acid type catalysts) 0.5 2.5 --
-- 1 2.9 2.5 2.4 2 4.2 -- -- 2.5 -- 3.4 4.3 3 4.3 -- -- 5 4.6 3.9
4.5 7.5 -- 4.4 4.5 10 -- -- 4.5 15 -- -- 4.7 Untreated 1.0 1.0 1.0
______________________________________
EXAMPLE 2
A treatment solution was prepared such that each 100 g contained 9
g DMDHEU and 9 millimoles of chloromethylphosphonic acid.
Cotton printcloth samples were impregnated and dried following the
procedure of Example 1. Samples were cured according to the
conditions listed in Table II, then evaluated for DP after tumble
drying.
TABLE II ______________________________________ Curing temp. DP
Rating after: .degree. C 1.5 min. cure 3 min. cure
______________________________________ 100 -- 2.5 120 2.6 3.2 140
3.3 3.5 160 3.7 3.7 175 4.6 -- Untreated 1.0 1.0
______________________________________
Based upon the above-mentioned generally recognized minimum
acceptable DP rating of 3, it is shown in Table II that a 1.5 min.
curing time at 140.degree. C and higher is sufficient to produce a
3 rating or a 3 minute curing time is satisfactory at 120.degree.
C. The choice of curing temperatures is particularly important to
finishers desiring to affect energy conservation in their textile
operations. In every sample dimensional stability is increased over
that of the untreated fabric. The wide range of effective curing
temperatures demonstrates the versatility operative with these
phosphonic acid derivatives.
EXAMPLE 3
Treatment solutions were prepared such that each 100 g of solution
contained 15 g of DMDHEU with a catalyst. The catalyst
concentrations in the treatment baths, shown in Table III, were
prepared as in Example 1 by pipetting in stock solutions.
Cotton printcloth samples were passed into and through the
treatment baths and through squeeze rolls to achieve wet pickups of
about 90%. The wet, impregnated fabrics were pinned on frames
then:
Mild cure processing was done by heating the samples for 2.5
minutes at 100.degree. C, then washing and tumble drying;
Damp cure processing was done by drying fabrics for 20 minutes at
35.degree. C to reduce moisture content to 7-12%, sealing the
framed samples in plastic bags and holding for 20 hours at ambient
room temperature of about 25.degree. C, then removing the samples
for washing and tumble drying.
TABLE III
__________________________________________________________________________
Mmol Catalyst Mild Cure Process Damp Cure Process per 100 g treat-
WRA, WRA Catalyst ment bath DP W+F %N DP W+F %N
__________________________________________________________________________
##STR8## 5 10 2.6 3.3 241 261 1.37 1.74 2.6 2.9 208 238 0.34 1.22
##STR9## 10 2.5 213 1.07 2.2 192 0.38 ##STR10## 5 10 3.7 3.6 273
279 1.62 1.68 3.3 3.5 257 270 1.43 1.59 ##STR11## 10 2.7 228 1.04
1.7 188 0.33 Untreated -- 1.3 190 -- 1.3 -- --
__________________________________________________________________________
Improved dimensional stability is achieved by all treatments but it
is only marginal when the two ammonium salts are used in the damp
cure process as seen by the DP ratings. At the 10 millimole
concentration chloromethylphosphonic acid is an acceptable catalyst
with DMDHEU for imparting DP properties employing the mild cure
process. Trichloromethylphosphonic acid is an effective catalyst in
both curing processes to develop DP ratings of 3 or higher when a
concentration of at least 5 millimoles per 100 g of treatment bath
is used.
This experiment further demonstrates the wide adaptability of
phosphonic acid derivatives to catalysis in finishing
processes.
EXAMPLE 4
To 4.8 g (25 millimoles) of phenylphosphonic acid was added 13.2 g
water. To this solution was added 14.3 g (25 millimoles) of aqueous
29.8% NH.sub.3. Immediately a white precipitate formed showing that
the monoammonium salt of the acid (ammonium acid phenylphosphonate)
was insoluble. Solubilization did not occur after standing for 8
days. To this mixture was added an additional 1.43 g (25
millimoles) of aqueous 29.8% NH.sub.3 and, on shaking, complete
dissolution occurred indicating that the diammonium salt was
soluble. Water was added to obtain a volume of 50 ml. This stock
solution contained 0.5 millimole of diammonium phenylphosphonate,
##STR12## per ml of solution.
Treatment solutions were prepared such that each 100 g contained 9
g of DMDHEU with a catalyst. The catalyst concentrations in the
treatment baths were prepared as in Example 1 by pipetting in stock
solutions of the free acid or the diammonium salt.
Cotton printcloth samples were passed into and through the
treatment baths and through squeeze rolls to achieve wet pickups of
about 90%. The wet, impregnated fabrics were then pinned on frames,
dried for 7 minutes at 60.degree. C and cured for 3 minutes at
160.degree. C. Fabric properties are shown in Table IV.
From Table IV it is seen that improved dimensional stability of
fabric is achieved over a wide concentration range for the free
acid and the diammonium salt. At least 2 millimoles of the free
acid per 100 g of treatment solution or 2.5 millimoles of the
diammonium salt are required to achieve the acceptable DP level of
3. These results demonstrate the utility of aromatic phosphonic
acids and their diammonium salts. Furthermore, their effectiveness
is not at the expense of greatly reduced fabric strength. For those
skilled in the art, strength losses of 50% or greater may be
expected on most cotton fabrics finished for improved durable press
properties.
TABLE IV ______________________________________ Catalyst
concentration, mmol/100 g treatment WRA Brk. str., % Str. bath DP
W+F W. lbs. loss ______________________________________
Phenylphosphonic acid 0.5 1.9 214 41.2 12.2 1 2.6 232 38.5 17.9 2
3.3 263 32.6 30.5 3 3.6 274 30.5 35.0 5 3.6 274 28.0 40.3
Diammonium salt of phenylphosphonic acid 1 2.3 225 43.5 7.2 2.5 3.3
252 35.8 23.7 5 3.6 261 32.9 29.9 7.5 3.6 264 32.0 31.8 10 3.7 263
31.6 32.6 15 3.7 264 30.4 35.2 Untreated 1.0 190 46.9 --
______________________________________
EXAMPLE 5
20 ml of 1.25 M (25 millimoles) methylphosphonic acid were pipetted
into a 50 ml volumetric flask containing 1.43 g of aqueous 29.8%
NH.sub.3 (25 millimoles) and then water was added to bring to
volume. This stock solution contained 0.5 millimole of ammonium
acid methylphosphonate, ##STR13## per ml of solution.
40 ml of 1.25 M (50 millimoles) methylphosphonic acid were pipetted
into a 50 ml volumetric flask containing 1.45 g (25 millimoles)
magnesium hydroxide and water was added to dilute to volume. This
stock solution contained 0.5 millimole of magnesium acid
methylphosphonate, ##STR14## per ml of solution.
Solutions were prepared such that in each 100 g there
contained:
Solution A -- 9 g DMDHEU and 2.5 millimoles of methylphosphonic
acid;
Solution B -- 15 g DMDHEU and 10 millimoles of methylphosphonic
acid;
Solution C -- 9 g DMDHEU and 10 millimoles of ammonium acid
methylphosphonate; and
Solution D -- 9 g DMDHEU and 10 millimoles of magnesium acid
methylphosphonate.
Sample A, a cotton printcloth, was passed into and through Solution
A then squeeze rolls to achieve a wet pickup of about 90%. The wet,
impregnated fabric was pinned on a frame, dried 7 minutes at
60.degree. C and cured 3 minutes at 160.degree. C.
Samples B-1 and B-2, cotton printcloth, were passed into and
through Solution B then squeeze rolls to achieve wet pickups of
about 90%. The wet, impregnated samples were then pinned on frames.
Sample B-1 was treated by the mild cure finishing process as in
Example 3 and Sample B-2 was treated by the damp cure process as in
Example 3.
Sample C, cotton printcloth, was passed into and through Solution C
then squeeze rolls to achieve a wet pickup of about 90%. The wet,
impregnated sample was pinned on a frame then treated as was Sample
A.
Sample D, cotton printcloth, was passed into and through Solution D
and processed as was Sample C.
All treated fabrics were then evaluated. Properties of samples are
shown in Table V.
TABLE V ______________________________________ WRA Sample %N DP W+F
______________________________________ A 1.08 4.3 277 B-1 1.77 3.8
271 B-2 1.28 3.3 249 C 1.05 3.7 279 D 1.01 4.0 287
______________________________________
Methylphosphonic acid is an effective catalyst for imparting
durable press properties to textiles by pad-dry-cure (Sample A),
mild cure (Sample B-1), and damp cure (Sample B-2) processes. All
DP ratings were above 3 and wrinkle recovery was greatly increased.
The extent of reaction, as measured by nitrogen content in the
finished samples, is high.
The ammonium acid salt (Sample C) and the magnesium acid salt
(Sample D) were excellent catalysts as shown in the above results.
It is of particular interest to note that the ammonium acid salt of
the alkyl phosphonate is an effective catalyst whereas the
corresponding ammonium acid aryl phosphonate of Example 4 was an
insoluble salt and thus not a useful catalyst for textile finishing
from aqueous baths.
EXAMPLE 6
The magnesium salt of methylphosphonic acid, ##STR15## was prepared
by adding 1.45 g (25 millimoles) magnesium hydroxide to 20 ml of
1.25 M (25 millimoles) methylphosphonic acid and then diluting the
solution to 50 ml with water. This stock solution contained 0.5
millimole of the magnesium salt per ml.
A treatment solution was prepared such that 100 g of solution
contained 9 g DMDHEU and 10 millimoles of the magnesium salt.
Sample E, a cotton printcloth and Sample F, a 50 polyester/50
cotton sheeting were processed in the treatment solution following
the procedure of Example 1.
DP ratings were 4.0 for Sample E and 4.3 for Sample F; nitrogen
contents of the finished fabrics were 1.08% for Sample E and 1.02%
for Sample F. The example demonstrates high reactivity as seen in
nitrogen contents with resultant high DP performances as seen in
the DP ratings. The catalyst is effective in the treatment of
fabric containing as little as 50% cotton.
EXAMPLE 7
An aqueous treatment solution was prepared such that each 100 g of
solution contained 0.5 g emulsified polyethylene, 0.1 g wetting
agent, 10 millimoles of catalyst, and 36 g of a mixture comprising
the molar ratio of 6:5:1 of tetrakis(hydroxymethyl)phosphonium
hydroxide (THPOH) to urea to trimethylol melamine (TMM),
respectively.
Cotton twill fabrics of approximately 8 oz per sq. yd. were passed
into and through the treatment solutions and squeeze rolls twice to
achieve wet pickups of about 105%. The wet, impregnated fabrics
were dried for 3 minutes at 85.degree. C, cured for 3 minutes at
160.degree. C, passed into and through a 2% aqueous H.sub.2 O.sub.2
solution, through squeeze rolls, rinsed in running tap water for 30
minutes, then dried for 3 minutes at 85.degree. C.
Sample G was treated with the solution containing phosphoric acid,
H.sub.3 PO.sub.4, catalyst;
Sample H was treated with the solution containing
chloromethylphosphonic acid, ##STR16## catalyst;
Sample I was treated with the solution containing phenylphosphonic
acid, ##STR17## catalyst;
Sample J was treated with the solution containing magnesium acid
methylphosphonate, ##STR18## catalyst.
All samples were flame resistant in that they passed the match test
at 180.degree..
Other results of treatments employing these catalysts are given in
Table VI.
TABLE VI ______________________________________ % % Wet %
Efficiency WRA Sample Pickup Add-on of add-on % P % N W+F
______________________________________ No catalyst 106 25.4 66.6
3.94 4.47 253 G 105 28.5 75.4 3.87 4.56 263 H 105 29.1 76.9 4.41
4.64 270 I 105 28.6 75.7 4.38 4.58 258 J 106 30.1 78.9 4.26 4.61
264 ______________________________________
It has been demonstrated, as seen in Table VI and in the match test
results, that phosphonic acid derivatives, Samples H, I, and J, are
catalytically as effective in finishing fabric with a flame
retardant as the mineral acid, phosphoric acid, Sample G, and,
surprisingly, greater bound phosphorus contents are achieved with
these phosphonic acid based catalysts than with phosphoric acid. It
is well known to those skilled in the art that high phosphorus
contents are important in achieving good durable textile flame
resistance. The efficiency of add-ons of the treatments catalyzed
by the phosphonic acid derivatives are comparable to that of
phosphoric acid and does not explain the unexpected increase in
phosphorus contents.
Wrinkle recovery angles, a measure of dimensional stability and
smooth drying performance in fabrics, also were surprisingly
high.
The example further demonstrates the wide versatility of these
catalytic agents.
* * * * *